China’s Jiangsu Top Composite Technology Co. Ltd. has developed what it says is the country’s first energy-saving window frame made with pultruded glass fiber reinforced polyurethane, in a partnership with Bayer MaterialScience. The new window frame retains heat and cold much more efficiently than aluminum, and is much stronger than both aluminum alloy and PVC, the companies said in a Dec. 13 news release. “The brand-new GRPU energy-saving window co-developed by Bayer and us demonstrates state-of-the-art technology combining environmental protection with low energy consumption,” said Feng Yi, president of Suzhou, Jiangsu province-based Jiangsu Top Composite. “The thermal transmission coefficient is only 1/700 of aluminum alloy, which means a massive amount of energy saved for households compared with the majority of window products in the market.” The window frame is pultruded with a zero volatile organic compound polyurethane from Bayer, which cuts energy consumption in half compared to an aluminum alloy model with the same design, the companies said. The firms said the window frames have a number of technical advantages, including a linear coefficient of thermal expansion that is similar to the surrounding walls, meaning that as temperatures change there are few gaps between the frames and walls; a bending strength two to three times aluminum alloys and 10 times PVC; and a bending modulus up to four times that of regular fiberglass-reinforced plastics.